<PAGE>

                                                                   EXHIBIT 10.13

                     SCHEDULE IDENTIFYING OMITTED DOCUMENTS

The only particulars in which the attached agreement differs from the omitted
agreements are the name of the officer who is a party to the agreement, the
annual base salary, the amount of severance, the amount of change of control
severance.

<TABLE>
<CAPTION>
                                            Change of
                     Annual                  Control
      Name        Base Salary   Severance   Severance
---------------   -----------   ---------   ---------
<S>               <C>           <C>         <C>
Rodger A. Brown   $   115,000   $ 115,000   $ 230,000
Brent L. Larson   $   135,000   $ 135,000   $ 270,000
</TABLE>

<PAGE>

                              EMPLOYMENT AGREEMENT

     This Employment Agreement is made and entered into effective as of January
1, 2004 (the "Effective Date"), by and between NEOPROBE CORPORATION, a Delaware
Corporation with a place of business at 425 Metro Place North, Suite 300,
Dublin, Ohio 43017-1367 (the "Company") and CARL M. BOSCH of Worthington, Ohio
(the "Employee").

     WHEREAS, the Company and the Employee entered into an Employment Agreement
effective as of April 1, 2000 (the "2000 Employment Agreement"); and

     WHEREAS, the Company and the Employee entered into an Employment Agreement
effective as of October 1, 2001 (the "2001 Employment Agreement"); and

     WHEREAS, the Company and the Employee entered amended the 2001 Employment
Agreement on August 1, 2002 (the "2001 Amendment");

     WHEREAS, the Company and the Employee entered into an Employment Agreement
effective as of February 1, 2003 (the "2003 Employment Agreement"); and

     WHEREAS, the Company and the Employee wish to establish new terms,
covenants, and conditions for the Employee's continued employment with the
Company through this agreement ("Employment Agreement").

     NOW, THEREFORE, in consideration of the mutual agreements herein set forth,
the parties hereto agree as follows:

     1.   DUTIES. From and after the Effective Date, and based upon the terms
          and conditions set forth herein, the Company agrees to employ the
          Employee and the Employee agrees to be employed by the Company, as
          Vice-President, Instrument Development and Operations of the Company
          and in such equivalent, additional or higher executive level position
          or positions as shall be assigned to him by the Company's President
          and CEO. While serving in such executive level position or positions,
          the Employee shall report to, be responsible to, and shall take
          direction from the President and CEO of the Company. During the Term
          of this Employment Agreement (as defined in Section 2 below), the
          Employee agrees to devote substantially all of his working time to the
          position he holds with the Company and to faithfully, industriously,
          and to the best of his ability, experience and talent, perform the
          duties that are assigned to him. The Employee shall observe and abide
          by the reasonable corporate policies and decisions of the Company in
          all business matters disclosed to employee.

          The Employee represents and warrants to the Company that Exhibit A
          attached hereto sets forth a true and complete list of (a) all
          offices, directorships and other positions held by the Employee in
          corporations and firms other than the Company and its subsidiaries and
          (b) any investment or ownership interest in any corporation or firm
          other than the Company beneficially owned by the Employee (excluding
          investments in life insurance policies, bank deposits, publicly traded
          securities that are less than five percent (5%) of their class and
          real estate). The Employee will promptly notify the Board of Directors
          of the Company of any additional positions undertaken or investments
          made by the Employee during the Term of this Employment Agreement if
          they are of a type that if they had existed on the date hereof, should
          have been listed on Exhibit A hereto. As long as the Employee's other
          positions or investments in other firms do not create a conflict of
          interest, violate the Employee's obligations under Section 7 below or
          cause the Employee to neglect his duties hereunder, such activities
          and positions shall not be deemed to be a breach of this Employment
          Agreement.

                                       -2-

<PAGE>

     2.   TERM OF THIS EMPLOYMENT AGREEMENT. Subject to Sections 4 and 5 hereof,
          the Term of this Employment Agreement shall be for a period of twelve
          (12) months, commencing January 1, 2004 and terminating December 31,
          2004.

     3.   COMPENSATION. During the Term of this Employment Agreement, the
          Company shall pay, and the Employee agrees to accept as full
          consideration for the services to be rendered by the Employee
          hereunder, compensation consisting of the following:

          A.   SALARY. Beginning on the first day of the Term of this Employment
               Agreement, the Company shall pay the Employee a salary of One
               Hundred Thirty-Five Thousand Dollars ($135,000) per year, payable
               in semi-monthly or monthly installments as requested by the
               Employee. Further, the Company agrees to review the Employee's
               base salary by July 1, 2004.

          B.   BONUS. The Compensation Committee of the Board of Directors will,
               on an annual basis, review the performance of the Company and of
               the Employee and will pay such bonus, as it deems appropriate, in
               its discretion, to the Employee based upon such review. Such
               review and bonus shall be consistent with any bonus plan adopted
               by the Compensation Committee, which covers the executive
               officers and employees of the Company generally.

          C.   BENEFITS. During the Term of this Employment Agreement, the
               Employee will receive such employee benefits as are generally
               available to all employees of the Company.

          D.   STOCK OPTIONS. The Compensation Committee of the Board of
               Directors may, from time-to-time, grant stock options, restricted
               stock purchase opportunities and such other forms of stock-based
               incentive compensation as it deems appropriate, in its
               discretion, to the Employee under the Company's Stock Option and
               Restricted Stock Purchase Plan and the 1996 Stock Incentive Plan
               (the "Stock Plans"). The terms of the relevant award agreements
               shall govern the rights of the Employee and the Company
               thereunder in the event of any conflict between such agreement
               and this Employment Agreement.

          E.   VACATION. The Employee shall be entitled to twenty (20) days of
               vacation during each calendar year during the Term of this
               Employment Agreement.

          F.   EXPENSES. The Company shall reimburse the Employee for all
               reasonable out-of-pocket expenses incurred by him in the
               performance of his duties hereunder, including expenses for
               travel, entertainment and similar items, promptly after the
               presentation by the Employee, from time-to-time, of an itemized
               account of such expenses.

     4.   TERMINATION.

          A.   FOR CAUSE. The Company may terminate the employment of the
               Employee prior to the end of the Term of this Employment
               Agreement "for cause." Termination "for cause" shall be defined
               as a termination by the Company of the employment of the Employee
               occasioned by the failure by the Employee to cure a willful
               breach of a material duty imposed on the Employee under this
               Employment Agreement within 15 days after written notice thereof
               by the Company or the continuation by the Employee after written
               notice by the Company of a willful and continued neglect of a
               duty imposed on the Employee under this Employment Agreement. In
               the event of termination by the Company "for cause," all salary,
               benefits and other payments shall cease at the time of
               termination, and the Company shall have no further obligations to
               the Employee.

          B.   RESIGNATION. If the Employee resigns for any reason, all salary,
               benefits and other payments (except as otherwise provided in
               paragraph G of this Section 4 below) shall cease at the time such
               resignation becomes effective. At the time of any such
               resignation, the Company shall pay the Employee the value of any
               accrued but unused vacation time, and the amount of all

                                       -3-

<PAGE>

               accrued but previously unpaid base salary through the date of
               such termination, excluding any salary deferred under paragraph A
               of Section 3 above. The Company shall promptly reimburse the
               Employee for the amount of any expenses incurred prior to such
               termination by the Employee as required under paragraph G of
               Section 3 above.

          C.   DISABILITY, DEATH. The Company may terminate the employment of
               the Employee prior to the end of the Term of this Employment
               Agreement if the Employee has been unable to perform his duties
               hereunder for a continuous period of six (6) months due to a
               physical or mental condition that, in the opinion of a licensed
               physician, will be of indefinite duration or is without a
               reasonable probability of recovery. The Employee agrees to submit
               to an examination by a licensed physician of his choice in order
               to obtain such opinion, at the request of the Company, made after
               the Employee has been absent from his place of employment for at
               least six (6) months. The Company shall pay for any requested
               examination. However, this provision does not abrogate either the
               Company's or the Employee's rights and obligations pursuant to
               the Family and Medical Leave Act of 1993, and a termination of
               employment under this paragraph C shall not be deemed to be a
               termination for cause.

               If during the Term of this Employment Agreement, the Employee
               dies or his employment is terminated because of his disability,
               all salary, benefits and other payments shall cease at the time
               of death or disability, provided, however, that the Company shall
               provide such health, dental and similar insurance or benefits as
               were provided to Employee immediately before his termination by
               reason of death or disability, to Employee or his family for the
               longer of twelve (12) months after such termination or the full
               unexpired Term of this Employment Agreement on the same terms and
               conditions (including cost) as were applicable before such
               termination. In addition, for the first six (6) months of
               disability, the Company shall pay to the Employee the difference,
               if any, between any cash benefits received by the Employee from a
               Company-sponsored disability insurance policy and the Employee's
               salary hereunder in accordance with paragraph A of Section 3
               above. At the time of any such termination, the Company shall pay
               the Employee, the value of any accrued but unused vacation time,
               and the amount of all accrued but previously unpaid base salary
               through the date of such termination. The Company shall promptly
               reimburse the Employee for the amount of any expenses incurred
               prior to such termination by the Employee as required under
               paragraph G of Section 3 above.

          D.   TERMINATION WITHOUT CAUSE. A termination without cause is a
               termination of the employment of the Employee by the Company that
               is not "for cause" and not occasioned by the resignation, death
               or disability of the Employee. If the Company terminates the
               employment of the Employee without cause, (whether before the end
               of the Term of this Employment Agreement or, if the Employee is
               employed by the Company under paragraph E of this Section 4
               below, after the Term of this Employment Agreement has ended) the
               Company shall, at the time of such termination, pay to the
               Employee the severance payment provided in paragraph F of this
               Section 4 below together with the value of any accrued but unused
               vacation time and the amount of all accrued but previously unpaid
               base salary through the date of such termination and shall
               provide him with all of his benefits under paragraph C of Section
               3 above for the longer of twelve (12) months or the full
               unexpired Term of this Employment Agreement. The Company shall
               promptly reimburse the Employee for the amount of any expenses
               incurred prior to such termination by the Employee as required
               under paragraph F of Section 3 above.

               If the Company terminates the employment of the Employee because
               it has ceased to do business or substantially completed the
               liquidation of its assets or because it has relocated to another
               city and the Employee has decided not to relocate also, such
               termination of employment shall be deemed to be without cause.

          E.   END OF THE TERM OF THIS EMPLOYMENT AGREEMENT. Except as otherwise
               provided in paragraphs F and G of this Section 4 below, the
               Company may terminate the employment of

                                       -4-

<PAGE>

               the Employee at the end of the Term of this Employment Agreement
               without any liability on the part of the Company to the Employee
               but, if the Employee continues to be an employee of the Company
               after the Term of this Employment Agreement ends, his employment
               shall be governed by the terms and conditions of this Agreement,
               but he shall be an employee at will and his employment may be
               terminated at any time by either the Company or the Employee
               without notice and for any reason not prohibited by law or no
               reason at all. If the Company terminates the employment of the
               Employee at the end of the Term of this Employment Agreement, the
               Company shall, at the time of such termination, pay to the
               Employee the severance payment provided in paragraph F of this
               Section 4 below together with the value of any accrued but unused
               vacation time and the amount of all accrued but previously unpaid
               base salary through the date of such termination. The Company
               shall promptly reimburse the Employee for the amount of any
               reasonable expenses incurred prior to such termination by the
               Employee as required under paragraph F of Section 3 above.

          F.   SEVERANCE. If the employment of the Employee is terminated by the
               Company, at the end of the Term of this Employment Agreement or,
               without cause (whether before the end of the Term of this
               Employment Agreement or, if the Employee is employed by the
               Company under paragraph E of this Section 4 above, after the Term
               of this Employment Agreement has ended), the Employee shall be
               paid, as a severance payment at the time of such termination, the
               amount of One Hundred Thirty-Five Thousand Dollars ($135,000)
               together with the value of any accrued but unused vacation time.

          G.   CHANGE OF CONTROL SEVERANCE. In addition to the rights of the
               Employee under the Company's employee benefit plans (paragraphs C
               of Section 3 above) but in lieu of any severance payment under
               paragraph F of this Section 4 above, if there is a Change in
               Control of the Company (as defined below) and the employment of
               the Employee is concurrently or subsequently terminated (a) by
               the Company without cause, (b) by the expiration of the Term of
               this Employment Agreement, or (c) by the resignation of the
               Employee because he has reasonably determined in good faith that
               his titles, authorities, responsibilities, salary, bonus
               opportunities or benefits have been materially diminished, that a
               material adverse change in his working conditions has occurred,
               that his services are no longer required in light of the
               Company's business plan, or the Company has breached this
               Employment Agreement, the Company shall pay the Employee, as a
               severance payment, at the time of such termination, the amount of
               Two Hundred Seventy Thousand Dollars ($270,000) together with the
               value of any accrued but unused vacation time, and the amount of
               all accrued but previously unpaid base salary through the date of
               termination and shall provide him with all of this benefits under
               paragraph C of Section 3 above for the longer of twelve (12)
               months or the full unexpired Term of this Employment Agreement.
               The Company shall promptly reimburse the Employee for the amount
               of any expenses incurred prior to such termination by the
               Employee as required under paragraph F of Section 3 above.

               For the purpose of this Employment Agreement, a Change in Control
               of the Company has occurred when: (a) any person (defined for the
               purposes of this paragraph G to mean any person within the
               meaning of Section 13 (d) of the Securities Exchange Act of 1934
               (the "Exchange Act")), other than Neoprobe or an employee benefit
               plan created by its Board of Directors for the benefit of its
               employees, either directly or indirectly, acquires beneficial
               ownership (determined under Rule 13d-3 of the Regulations
               promulgated by the Securities and Exchange Commission under
               Section 13(d) of the Exchange Act) of securities issued by
               Neoprobe having thirty percent (30%) or more of the voting power
               of all the voting securities issued by Neoprobe in the election
               of Directors at the next meeting of the holders of voting
               securities to be held for such purpose; (b) a majority of the
               Directors elected at any meeting of the holders of voting
               securities of Neoprobe are persons who were not nominated for
               such election by the Board of Directors or a duly constituted
               committee of the Board of Directors having authority in such
               matters; (c) the stockholders of Neoprobe approve a merger or
               consolidation of Neoprobe with another person other than a merger
               or consolidation in which the holders of Neoprobe's voting
               securities issued and outstanding immediately before such

                                       -5-

<PAGE>

               merger or consolidation continue to hold voting securities in the
               surviving or resulting corporation (in the same relative
               proportions to each other as existed before such event)
               comprising eighty percent (80%) or more of the voting power for
               all purposes of the surviving or resulting corporation; or (d)
               the stockholders of Neoprobe approve a transfer of substantially
               all of the assets of Neoprobe to another person other than a
               transfer to a transferee, eighty percent (80%) or more of the
               voting power of which is owned or controlled by Neoprobe or by
               the holders of Neoprobe's voting securities issued and
               outstanding immediately before such transfer in the same relative
               proportions to each other as existed before such event. The
               parties hereto agree that for the purpose of determining the time
               when a Change of Control has occurred that if any transaction
               results from a definite proposal that was made before the end of
               the Term of this Employment Agreement but which continued until
               after the end of the Term of this Employment Agreement and such
               transaction is consummated after the end of the Term of this
               Employment Agreement, such transaction shall be deemed to have
               occurred when the definite proposal was made for the purposes of
               the first sentence of this paragraph G of this Section 4.

          H.   BENEFIT AND STOCK PLANS. In the event that a benefit plan or
               Stock Plan which covers the Employee has specific provisions
               concerning termination of employment, or the death or disability
               of an employee (e.g., life insurance or disability insurance),
               then such benefit plan or Stock Plan shall control the
               disposition of the benefits or stock options.

     5.   PROPRIETARY INFORMATION AGREEMENT. Employee has executed a Proprietary
          Information Agreement as a condition of employment with the Company.
          The Proprietary Information Agreement shall not be limited by this
          Employment Agreement in any manner, and the Employee shall act in
          accordance with the provisions of the Proprietary Information
          Agreement at all times during the Term of this Employment Agreement.

     6.   NON-COMPETITION. Employee agrees that for so long as he is employed by
          the Company under this Employment Agreement and for one (1) year
          thereafter, the Employee will not:

          A.   enter into the employ of or render any services to any person,
               firm, or corporation, which is engaged, in any part, in a
               Competitive Business (as defined below);

          B.   engage in any directly Competitive Business for his own account;

          C.   become associated with or interested in through retention or by
               employment any Competitive Business as an individual, partner,
               shareholder, creditor, director, officer, principal, agent,
               employee, trustee, consultant, advisor, or in any other
               relationship or capacity; or

          D.   solicit, interfere with, or endeavor to entice away from the
               Company, any of its customers, strategic partners, or sources of
               supply.

          Nothing in this Employment Agreement shall preclude Employee from
          taking employment in the banking or related financial services
          industries nor from investing his personal assets in the securities or
          any Competitive Business if such securities are traded on a national
          stock exchange or in the over-the-counter market and if such
          investment does not result in his beneficially owning, at any time,
          more than one percent (1%) of the publicly-traded equity securities of
          such Competitive Business. "Competitive Business" for purposes of this
          Employment Agreement shall mean any business or enterprise which:

          a.   is engaged in the development and/or commercialization of gamma
               radiation detection products and/or systems for use in
               intraoperative detection of cancer, or

          b.   reasonably understood to be competitive in the relevant market
               with products and/or systems described in clause a above, or

                                       -6-

<PAGE>

          c.   the Company engages in during the Term of this Employment
               Agreement pursuant to a determination of the Board of Directors
               and from which the Company derives a material amount of revenue
               or in which the Company has made a material capital investment.

          The covenant set forth in this Section 6 shall terminate immediately
          upon the substantial completion of the liquidation of assets of the
          Company or the termination of the employment of the Employee by the
          Company without cause or at the end of the Term of this Employment
          Agreement.

     7.   ARBITRATION. Any dispute or controversy arising under or in connection
          with this Employment Agreement shall be settled exclusively by
          arbitration in Columbus, Ohio, in accordance with the non-union
          employment arbitration rules of the American Arbitration Association
          ("AAA") then in effect. If specific non-union employment dispute rules
          are not in effect, then AAA commercial arbitration rules shall govern
          the dispute. If the amount claimed exceeds $100,000, the arbitration
          shall be before a panel of three arbitrators. Judgment may be entered
          on the arbitrator's award in any court having jurisdiction. The
          Company shall indemnify the Employee against and hold him harmless
          from any attorney's fees, court costs and other expenses incurred by
          the Employee in connection with the preparation, commencement,
          prosecution, defense, or enforcement of any arbitration, award,
          confirmation or judgment in order to assert or defend any right or
          obtain any payment under paragraph C of Section 4 above or under this
          sentence; without regard to the success of the Employee or his
          attorney in any such arbitration or proceeding.

     8.   GOVERNING LAW. The Employment Agreement shall be governed by and
          construed in accordance with the laws of the State of Ohio.

     9.   VALIDITY. The invalidity or unenforceability of any provision or
          provisions of this Employment Agreement shall not affect the validity
          or enforceability of any other provision of the Employment Agreement,
          which shall remain in full force and effect.

     10.  ENTIRE AGREEMENT.

          A.   The 2000, 2001 and 2003 Employment Agreements and the 2001
               Amendment are terminated as of the effective date of this
               Employment Agreement, except that awards under the Stock Plans
               granted to the Employee in the 2000, 2001 and 2003 Employment
               Agreements and the 2001 Amendment or in any previous employment
               agreement or by the Compensation Committee remain in full force
               and effect.

          B.   This Employment Agreement constitutes the entire understanding
               between the parties with respect to the subject matter hereof,
               superseding all negotiations, prior discussions, and preliminary
               agreements. This Employment Agreement may not be amended except
               in writing executed by the parties hereto.

     11.  EFFECT ON SUCCESSORS OF INTEREST. This Employment Agreement shall
          inure to the benefit of and be binding upon heirs, administrators,
          executors, successors and assigns of each of the parties hereto.
          Notwithstanding the above, the Employee recognizes and agrees that his
          obligation under this Employment Agreement may not be assigned without
          the consent of the Company.

IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Employment Agreement as of the date first written above.

NEOPROBE CORPORATION                                  EMPLOYEE

By: /s/ David C. Bupp                                 /s/ Carl. M. Bosch
   ------------------------------------------         --------------------------
    David C. Bupp, President and CEO                  Carl M. Bosch

                                       -7-